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Old 03-11-2011, 02:18 PM
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Re: TPS adjustment oddity

Quote:
Originally Posted by j cAT View Post
I would say this is because the TPS is defective. what can cause this is carb cleaner. this corrodes the electrical parts. as mentioned this component has had many failures. carb cleaner is usually the cause.

as the resistor [tps] gets hotter the resistance increases this means a lower voltage. most likely 5 volts is locked at 5volts.

with all power voltage /connector removed move the tps and measure the resistance . use a non digital meter is best see if the movement causes a loss of continuity.[open circuit]

5.oL engine it should be .5volts....
I measured the resistance w/ my analog meter and I didn't find any flat spots (i.e. infinite resistance or near zero resistance) but it was a bit "bouncy" for lack of a better word. When I carefully had the throttle nearer and nearer to WOT it would increase in resistance slowly but as I barely inched it further it would decrease and then increase and sometimes decrease quite a bit.

This also happened with my orig. TPS but I have never used carb cleaner since I installed the new one about a year ago or less... Did I just buy another defective TPS?

CD Smalley, the input source voltage stays at 5.02volts exactly no matter if the engine is on or off or if the throttle changes. When I disconnect the connector to the tps and then check the source voltage (from the connector itself of course) it reads 4.82 volts but does not change.
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